KR20120096637A - Double rotor and single stator type bldc motor - Google Patents

Abstract

A double rotor and single stator type BLDC motor is disclosed.
In the double rotor and single stator type BLDC motor according to the embodiment of the present invention, the motor casing rotates around the motor shaft, and is disposed at the rear of the motor casing, and the casing body in which the internal rotor and the external rotor are integrally formed. A stator disposed between the casing cover coupled to the casing body in front of the motor casing, the inner magnet arranged on the inner rotor and the outer magnet arranged on the outer rotor, and coupled to the motor shaft. And a control unit installed in the stator and controlling the motor, wherein the inner magnet or the outer magnet is pressurized and fixed by an elastic step formed on the inner rotor or the back yoke for the outer rotor. have.

Description

DOUBLE ROTOR AND SINGLE STATOR TYPE BLDC MOTOR

The present invention relates to a brushless DC (BLDC) motor, and more particularly, to improve the assemblability by pressing the magnet to be fixed to the elastic stepped portion, good heat dissipation, initial mobility is smooth double rotor and single stator type Relates to a BLDC motor.

In general, BLDC motors are used in various fields including high speed and precision machinery because of their high efficiency and ease of control.

BLDC motors perform electrical rectification using switch elements instead of mechanical rectification through commutators.

For example, a BLDC motor includes a control unit having a power supply device such as a switching mode power supply (SMPS), a switching device driver, and a switching device.

Here, the power supply device converts an AC voltage, which is a commercial power input from the outside, into a DC voltage. The switching device driver generates a switching control signal by receiving the DC voltage converted from the power supply.

The switching element converts the DC voltage applied from the power supply device into a three-phase voltage according to the switching control signal and applies it to the winding of the stator core of the stator for the BLDC motor. In this case, the winding of the stator core generates a magnetic field by rotating the rotor of the motor by the three-phase voltage.

However, when the BLDC motor according to the prior art has a dual rotor type, the inner rotor, the outer rotor, and the rotor cover are separately manufactured and then assembled, and thus the assemblability is relatively low, compared to the rotor integrated structure. Concentricity management is also a disadvantage.

In addition, the BLDC motor according to the related art has a disadvantage in that the core installation work is complicated and the work time is relatively long as the fixed stator core is simply fixed and installed along the ring-shaped stator core support plate.

In addition, the BLDC motor according to the prior art has a disadvantage in that the heat dissipation characteristics are inferior because the surface area of the heat dissipation is relatively narrow since the capping member is simply fixed to the stator core support plate and no cap member is used.

In addition, the BLDC motor according to the prior art has only a single stator core support plate, which is relatively difficult to compensate for magnetic loss.

In addition, the BLDC motor according to the prior art, when the dual rotor type, may be composed of the inner rotor and the outer rotor with the magnets are arranged, respectively, compared to the single rotor type, the inner pole and the outer rotor of the S pole of the inner rotor Due to the simple installation of the N-pole external magnet corresponding to the arrangement position of the winding of the stator core, initial starting is not smooth.

In addition, the BLDC motor according to the related art forms a magnetic field in the air gap by using a permanent magnet instead of a field coil, so that cogging torque, which is a non-uniform torque of the stator, may be generated, and torque ripple during operation. There is a disadvantage that large ripple) appears.

In addition, the BLDC motor according to the prior art has a disadvantage in that the assembling is relatively inferior because the stator cores are separately manufactured and arranged to be assembled.

In addition, the BLDC motor according to the prior art is exposed to the heat generated from the BLDC motor, it is difficult to easily release the heat transferred to the control unit.

In addition, the BLDC motor according to the related art has a disadvantage in that installation of a plurality of Hall sensors or Hall ICs is very inconvenient, such as fixing the Hall IC to a reference position and electrically connecting the Hall IC to the control unit. .

Embodiment of the present invention is to provide a BLDC motor that can be easily fixed to the magnet by using the elastic step portion formed on the inner rotor or the outer rotor back yoke, respectively, to improve the assembly of the magnet.

In addition, an embodiment of the present invention is to provide a BLDC motor that facilitates the assembly work of the stator core by the stator frame portion and the cap portion, and induce a heat dissipation effect by the cap portion as well as the stator frame portion.

In addition, an embodiment of the present invention is to provide a BLDC motor capable of compensating the stator magnetic loss by a pair of stator frame portion and the cap portion.

In addition, an embodiment of the present invention is to provide a BLDC motor smooth initial mobility.

In addition, an embodiment of the present invention is to provide a BLDC motor that can be easily assembled between the stator core and the stator frame portion and the cap portion.

In addition, an embodiment of the present invention is to provide a BLDC motor having good heat dissipation characteristics and installation of the control unit.

In addition, an embodiment of the present invention is to provide a BLDC motor that is easy to install a plurality of Hall ICs with a control unit.

According to an aspect of the present invention, a BLDC motor in which a motor casing rotates around a motor shaft, the casing body disposed behind the motor casing and integrally formed with an internal rotor and an external rotor, and the motor A stator disposed between a casing cover coupled to the casing body at a front of the casing, an inner magnet arranged on the inner rotor and an outer magnet arranged on the outer rotor, and a stator coupled to the motor shaft; A control unit for controlling the motor, wherein the inner magnet or the outer magnet is press-fixed by an elastic step formed in the inner rotor or the back yoke for the outer rotor. A double rotor and a single stator type BLDC motor can be provided.

In addition, the elastic stepped portion may be formed on the outer yoke or inner yoke to form a pair for each of the outer magnet or the inner magnet.

The elastic stepped part may include an elastic support part protruding from the surface of the outer yoke or the inner back yoke, and an inclined stepped part protruding from an end of the elastic support part and having an inclined surface on the outer part.

The elastic stepped portion may form an inclined stepped portion gap between the elastic support for one magnet and the elastic support for the other magnet.

The elastic stepped portion may be integrally formed with the outer yoke or the inner yoke, or may be separately manufactured and then incorporated by insert injection in the manufacturing process of the outer yoke or the inner yoke.

Further, between the outer yoke and the outer magnet, between the elastic step portion for the outer magnet and the outer magnet, between the inner back yoke and the inner magnet, between the elastic step portion for the inner magnet and the inner magnet. The adhesive layer may be further interposed.

Embodiment of the present invention is arranged in a plurality of pairs of elastic step portion in the inner rotor or the outer rotor back yoke, respectively, along the circumferential direction of the inner rotor or the outer rotor, and each of the elastic stepped to secure the magnet between There is an advantage that can improve the assembly.

In addition, the embodiment of the present invention has the advantage of generating a bearing force by the physical structure, such as elastic stepped portion with respect to the rotational force direction of the inner rotor and the outer rotor, it is possible to prevent the magnetic separation failure.

In addition, the embodiment of the present invention has an advantage of facilitating the assembly process of the stator core by a pair of stator frame portion and the cap portion.

In addition, the embodiment of the present invention may be made of a pair of stator frame portion and the cap portion of the aluminum alloy material, the heat dissipation characteristics are very high as it is mounted in the mounting groove of the stator frame portion and the cap portion in direct contact with the stator core There is an advantage to implement a good, lightweight structure.

In addition, the embodiment of the present invention, as the stator core is disposed between the pair of stator frame portion and the cap portion, there is an advantage that can compensate for the stator magnetic losses.

In addition, in the embodiment of the present invention, since the N pole outer magnet of the outer rotor corresponding to the S pole inner magnet of the inner rotor is not aligned with the imaginary reference line and is displaced, the initial maneuverability is smooth and the operation is performed. When the torque ripple (torque ripple) can be reduced.

That is, the embodiment of the present invention can increase the motor mobility through the magnet arrangement to the predetermined magnet arrangement angle of the S pole of the inner rotor and the N pole of the outer rotor with the stator core at the center.

In addition, the embodiment of the present invention has the advantage that can reduce the motor vibration and noise in accordance with the torque ripple reduction.

In addition, the embodiment of the present invention, since the core connection is formed between the stator core and the other stator core, a plurality of stator cores can be continuously connected by the core connecting portion, thereby facilitating the plurality of stator cores interconnected as a plurality There is an advantage that can be assembled easily.

In addition, since the embodiment of the present invention forms a bent portion thinner than the core connecting portion, when the stator cores are arranged and coupled along the circumferential direction in the inner space of the stator frame portion and the cap portion, the bending is made based on the bent portion. Therefore, the deformation | transformation of parts other than a bending part can be prevented.

Accordingly, in the embodiment of the present invention, the stator core can be assembled between the stator frame portion and the cap portion while taking a stable posture without twisting.

In addition, since a through hole penetrated in the thickness direction of the stator core is further formed at a portion connected to the core connecting portion in the middle portion of each stator core, magnetic leakage is minimized by the through hole.

In addition, the embodiment of the present invention is a structure for assembling a control unit having a power supply device, a switching device driver, and a switching device directly to the stator, there is an advantage that the heat dissipation characteristics and installation of the control unit is good.

That is, as the control unit is assembled to the stator frame unit with the heat dissipation pad interposed therebetween, heat generated from the control unit may be transmitted and distributed to the stator frame unit or the cap unit or may be discharged to the outside through a motor shaft coupled to the frame unit. There is an advantage.

In addition, the embodiment of the present invention has the advantage that the control unit is mounted on the stator frame portion, a simple motor configuration without the need to install the control unit externally.

In addition, according to the embodiment of the present invention, a plurality of Hall ICs or Hall sensors protrude from the PCB of the controller so as to be electrically connected to the PCB of the controller. There is an advantage in that a plurality of Hall ICs or Hall sensors are easily installed.

In addition, the embodiment of the present invention is further equipped with a Hall sensor for reverse rotation with the Hall IC, and by specifying the sequence number of the Hall sensor to check the sensor input order or number, the electric with the BLDC motor of the present invention There is an advantage that can provide anti-rolling function to the car or electric motorcycle.

1 is a perspective view of a double rotor and a single stator type BLDC motor according to an embodiment of the present invention.
Figure 2 is an exploded perspective view of the casing cover shown in FIG.
3 is a perspective view of a casing body in which the inner rotor and the outer rotor shown in FIG. 1 are integrally formed.
4 is an exploded perspective view of a magnet showing the elastic step illustrated in FIG. 3.
5 is a rear perspective view of the stator to be installed inside the motor.
6 is a front side perspective view of the stator shown in FIG. 5;
7 is an exploded perspective view of the stator frame portion and the stator and cap portion.
8 is a plan view illustrating an arrangement relationship between a stator, an internal rotor, and an external rotor.
9 is a plan view for explaining the stator core for the stator.
FIG. 10 is a cross-sectional view illustrating an assembling state and a method of operating the double rotor and single stator type BLDC motor shown in FIG. 1.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

1 is a perspective view of a double rotor and a single stator type BLDC motor according to an embodiment of the present invention.

Referring to FIG. 1, the present embodiment is a hub type driving motor for driving a place of use (eg, an electric vehicle, an electric motorcycle, and an electric bicycle), and is fixed to a motor coupling position that is an installation position of the place of use. It may be a double rotor and a single stator type BLDC motor in which a motor casing rotates around the motor shaft 120.

Here, the double rotor may refer to the inner rotor and the outer rotor, and the single stator may refer to a single stator between the inner rotor and the outer rotor.

In addition, the motor casing may include a casing body 100 disposed at the rear of the motor casing, and a casing cover 110 disposed at the front of the motor casing and coupled to the casing body 100.

This embodiment is a BLDC motor that can operate by applying a voltage in the form of a pulse width modulation (PWM) waveform. A motor having a high duty ratio has a strong motor driving force, and a small duty ratio has a weak motor driving force. It may include a control unit 300 (see Fig. 5 or 6) having a drive circuit.

Here, the control unit 300 may be installed inside the casing body 100, and may be configured to adjust the rotational speed of the double rotor and single stator type BLDC motor by adjusting the duty ratio of PWM.

That is, the control unit 300 may be composed of a general double rotor and a single stator type BLDC motor control circuit element. In addition, the control unit 300 may be configured to alternately apply a voltage, that is, a positive voltage and a negative voltage, to the windings of the stator core when the isostatic period of the counter electromotive force.

In addition, the present embodiment includes a casing body 100 integrally formed by integrating the body rear portion, the inner rotor and the outer rotor, and a casing cover 110 that is assembled to block the opened portion of the casing body 100. can do.

According to the operation control of the controller 300, the motor casing including the casing body 100 and the casing cover 110 can be rotated about the motor shaft 120 on the virtual center line CL. .

The power line for applying power to the control unit 300 may be electrically connected to the power input terminal of the control unit 300 through an inlet hole formed in the rear side of the motor shaft 120.

Structural portions of the casing body 100 (eg, body back portion, outer wall, inner wall, outer ring protrusion) and the casing cover 110 are each manufactured by die casting using aluminum alloy material, or powder metallurgy using tungsten material. It may be molded into.

The casing body 100 coupled with the casing cover 110 is integrally formed by integrating the body rear portion, the inner rotor and the outer rotor, and as a hub for driving an electric vehicle, an electric motorcycle, and an electric bicycle. It can exert structural stiffness that can withstand shock, vibration, dynamic and static loads.

Figure 2 is an exploded perspective view of the casing cover shown in FIG.

Referring to FIG. 2, the casing cover 110 is configured to be disassembled and assembled with the casing body 100 shown in FIG. 1.

The casing cover 110 may be disassembled for insertion and assembly of the internal components of the casing body 100 and maintenance.

To this end, the casing cover 110 is formed of a circular disk-shaped cover body 111 that can cover the open portion of the casing body 100, protruded to the outer edge of the cover body 110 and spaced along the circumferential direction A plurality of bolted fastening portions 112 formed to maintain the spacing, respectively forming a fastening hole, a bearing seat portion 113 formed at the center of the cover body 110, and a bearing 114 of the bearing seat portion 113. ) May include a ring plate 115 that is attachably attachable while covering the bearing seat 113.

In order to couple between the ring plate 115 and the bearing seat 113, a plurality of fastening holes are formed around the center through-hole of the ring plate 115 and around the bearing seat 113 to be fastened. They can be joined or separated from each other via bolts.

3 is a perspective view of a casing body in which the inner rotor and the outer rotor are integrally formed;

Referring to FIG. 3, the casing body 100 has a body rear portion 101 formed at the rear of the casing body 100 and a thickness direction of the body rear portion 101 at the outer side of the body rear portion 101 (eg, a motor shaft). The outer rotor 130 is formed based on the outer wall (103) protruding integrally along the (axial direction of) and the bearing seating portion 102 of the outer wall body 103 and the body rear portion 101 of the body back portion 101 It may include an inner rotor 150 formed based on the inner wall 105 integrally protruded to be parallel to the outer wall 103 in a position between.

In this case, the bearing seat 102 may be provided with a bearing 104 engaged with the motor shaft.

The outer circumferential surface of the outer wall body 103 may have a plurality of outer ring protrusions 107 and 108 extending along the circumferential direction of the outer wall body 103 and protruding in the radial direction of the outer wall body 103.

Here, the outer ring protrusions (107, 108) can extend the surface area of the casing body 100 and perform a role such as cooling fins or heatsinks (heatsink) that is responsible for the cooling efficiency, and, together with the hub-type drive motor ( When used as a hub type driving motor, it simultaneously plays the same role as a mounting table that can be mounted to a place of use (eg, an electric vehicle, an electric motorcycle, or an electric bicycle) through the installation holes 109 of the outer ring protrusions 107 and 108. can do.

In addition, a fastening seating part 106 corresponding to the bolt fastening part 112 of the casing cover 110 described above with reference to FIG. 2 may be formed in front of the front outer ring protrusion 107.

Each fastening seating part 106 is provided with a fastening hole corresponding to the fastening hole of the bolt fastening part 112 of the casing cover 110, and through the fastening bolt (not shown), the casing body 100 and the casing cover 110. ) Can be fastened so that it can be mounted.

An outer back yoke 131 may be formed on an inner circumferential surface of the outer wall 103.

In the outer yoke 131, a plurality of outer magnets 132 may be pressed and fixed by the elastic stepped parts 135 arranged while maintaining a predetermined interval along the inner circumferential surface of the outer yoke 131.

In addition, the outer wall body 103 may be further provided with a sensing magnet 160 that can be detected by the Hall IC or the Hall sensor mounted on the control unit.

An inner back yoke 151 may be formed on an outer circumferential surface of the inner wall 105.

A plurality of inner magnets 152 may be fixed to the inner back yoke 151 by elastic stepped portions 155 arranged at predetermined intervals along the outer circumferential surface of the inner back yoke 151.

The casing body 100 integrates the body rear portion 101, the inner rotor 150, and the outer rotor 130 in one piece, thereby simplifying the assembly process of the double rotor and single stator type BLDC motor. You can do it.

While maintaining the clearance between the inner magnet 152 of the inner rotor 150 and the outer magnet 132 of the outer rotor 130, the stator 200 of FIG. Can be.

4 is an exploded perspective view of a magnet showing the elastic step illustrated in FIG. 3.

Referring to FIG. 4, each of the corresponding magnets (eg, internal magnets) using an elastic step 135 formed on a back yoke (eg, inner back yoke or outer back yoke 131) for the inner rotor or the outer rotor. Alternatively, the external magnet 132 may be pressurized.

For ease of explanation, in FIG. 4, pressure fixing of the outer magnet 132 based on the outer yoke 131 may be described. That is, since the elastic stepped portion 155 of the inner bag yoke 151 shown in FIG. 3 may have the same or very similar operating principle as the elastic stepped portion 135 to be described later, it may be omitted.

The elastic stepped portion 135 of FIG. 4 may be formed in the outer yoke 131 so as to form a pair for each of the plurality of external magnets 132.

The elastic stepped part 135 may include an elastic support part 135a protruding from the surface of the outer yoke 131, and an inclined stepped part 135b protruding from an end of the elastic support part 135a.

The elastic support part 135a and the inclined stepped part 135b may be formed of a material having elasticity among metals or nonmetals.

In addition, the space between the elastic support portion 135a may mean a space between the protruding jaw portions of the inclined stepped portion 135b facing each other. The space between the elastic support 135a may be formed in consideration of the volume of the external magnet 132 to be fixed by pressure.

The outer portion of the inclined stepped portion 135b may be formed as an inclined surface 135c. In addition, it is preferable that an inclined stepped portion arrangement gap g is further formed between the elastic support part 135a for one magnet and the elastic support part 135d for the other magnet to avoid mutual interference when bending deformation occurs due to magnet pressure.

Here, the inclined surface 135c causes perturbation such as sliding contact during the pressure coupling of the outer magnet 132 or the inner magnet (not shown), so that the restorable bending deformation is generated in the elastic support 135a. can do.

Then, when the outer magnet 132 or the inner magnet is completely inserted into the inner portion of the inclined stepped portion 135b, the elastic support 135a is restored to its original shape, so that the inclined stepped portion 135b is the outer magnet 132 Or it is possible to fix the corner portion of the inner magnet.

To this end, the elastic stepped portion 135 may be integrally molded with the outer yoke 131 or may be separately formed and then incorporated by insert injection in the process of manufacturing the outer yoke 131.

In addition, for BLDC motors that require more robust magnet fixing, the adhesive layers 136 and 137 may be disposed between the outer yoke 131 and the outer magnet 132 or between the elastic step 135 for the outer magnet 132 and the outer portion. It may be further interposed between the magnets 132.

The adhesive layers 136 and 137 may be previously applied to a part of the surface of the external magnet 132 using a conventional adhesive injection method (eg, a spray method or an injection method) before pressing and fixing the external magnet 132.

Also, although not shown, for the inner rotor, an adhesive layer may be further interposed between the inner back yoke and the inner magnet, or between the elastic stepped portion and the inner magnet for the inner magnet.

Through this, the plurality of inner magnets or outer magnets 132 can be easily coupled to the inner rotor or outer rotor of the casing body.

5 is a rear side perspective view of the stator to be installed inside the motor, and FIG. 6 is a front side perspective view of the stator shown in FIG. 5.

Referring to FIG. 5, the stator 200 may be fixedly used to the motor shaft 120 of the double rotor and single stator type BLDC motor described above in FIG. 1.

The stator 200 includes a boss 211 for fixing to the motor shaft 120, a plurality of supports 212 formed on the outside of the boss 211, and an outer ring part 213 connected to be supported by the support 212. Along the circumferential direction between the stator frame portion 210 having a), the cap portion 220 having a ring shape as a size corresponding to the outer diameter of the outer ring portion 213, and the stator frame portion 210 and the cap portion 220. It may include a winding portion 230 having a plurality of stator cores 231 arranged to maintain a predetermined interval.

That is, the stator 200 is arranged to maintain a clearance between the inner magnets arranged on the inner rotor and the outer magnets arranged on the outer rotor, and the upper part of the winding part 230 installed in the stator frame part 210. Covered with a cap portion 22 (hangover), the stator frame portion 210 may be coupled to the motor shaft through the boss 211.

The stator frame portion 210 and the cap portion 220 of the stator 200 may be manufactured by a die casting method using an aluminum alloy material, or may be molded by a powder metallurgy method using a tungsten material.

Receiving grooves 214 and 224 are formed at portions of the outer ring portion 213 and the cap portion 220 of the stator frame portion 210 facing each other to settle each stator core 231 of the winding portion 230. have.

The seating grooves 214 and 224 may be formed corresponding to the number and arrangement positions of the stator cores 231.

The stator core 231 seated in each of the seating grooves 214 and 224 and in direct contact with each other may allow heat to be transferred and distributed through the stator frame portion 210 and the cap 220 having the seating grooves 214 and 224. do.

The outer ring portion 213 and the cap portion 220 of the stator frame portion 210 are stacked in a sandwich structure with the winding portion 230 interposed therebetween, and the outer ring portion (between the winding portions 230 along the circumferential direction) is formed between the outer ring portion 213 and the cap portion 220. 213 and a plurality of fastening holes 225 formed through the cap 220 and fastening means (not shown) (eg, fastening bolts and nut assemblies or rivets).

Accordingly, the present embodiment has an advantage that the heat dissipation characteristics are very good and a light weight structure can be realized.

On the other hand, the sensor groove 215 for mounting the Hall IC 310 (Hall IC) of the control unit 300 may be formed on the basis of some of the stator core 231 among the stator frame portion 210.

For example, the hall IC 310 may be configured to sense the sensing magnet 160 shown in FIG. 3 and may be used to control the motor operation.

When the control unit 300 is installed using the outer surface of the stator frame unit 210, the plurality of Hall ICs 310 protruding on the PCB of the control unit 300 so as to be electrically connected to the PCB of the control unit 300. Are fitted into the sensor grooves 215 of the stator frame portion 210 in a one-to-one correspondence, and can be easily assembled.

Each of the windings 230 includes an insulator 240, 241 (see FIG. 9 or FIG. 10) coupled to enclose an intermediate portion of each stator core 231, and a winding wire 250 wound on the insulator 240, 241. , 251 (see FIG. 9 or FIG. 10).

On the other hand, the boss 211 of the stator 200, the shaft hole 216 for inserting the motor shaft 120 shown in Figure 10 and the stator shaft connecting portion of the circular plate shape protruding from the circumferential surface of the motor shaft 120 A plurality of bolt holes 217 formed to coincide with the coupling holes 122 of the 121 may be further formed.

The stator 200 may have a shape similar to that of a wheel for an automobile when the stator frame part 210, the winding part 230, and the cap part 220 are all combined.

Referring to FIG. 6, a heat dissipation pad 320 may be further interposed between the outer surface of the stator frame unit 210 and the controller 300.

The heat dissipation pad 320 may be made of a silicon heat dissipation material to have a thin pad shape.

As the control unit 300 is assembled based on the stator frame unit 210, heat generated by the control unit 300 may be discharged through the heat dissipation silicon pad 320 and the stator frame unit 210.

In addition, the control unit 300 may be attached based on the stator 200 so that a separate control unit installation space may not be required.

In addition, the plurality of Hall ICs 310 protruding on the PCB of the controller 300 are directly inserted into the sensor grooves 215 of the stator frame 210 together with the assembly of the controller 300. ) And related assembly work can be facilitated.

Meanwhile, the plurality of Hall ICs 310 may be attached based on the stator 200 and may be used for driving a motor by sensing an N pole or an S pole of a magnet of the rotor.

In addition, the hall sensors 330 and 340 are installed in the control unit 300 in a manner similar to the hall IC 310 so as to sense the sensing magnet 160 as shown in FIG. It may be additionally mounted to the sensor grooves (215a, 215b).

That is, the sensor grooves 215a and 215b for mounting the hall sensors 330 and 340 are formed between the stator cores of the stator frame part 210, so that the controller 300 may be installed in the stator frame part 210. At this time, the hall sensors 330 and 340 may be engaged with the sensor grooves 215a and 215b.

Hall sensors 330 and 340 are sensors based on a hall effect, and are transistors for detecting a magnetic field of the sensing magnet 160 of FIG. 3, and are more sensitive than magnetodiodes and have a distribution or intensity of magnetic field. It can measure, downsizing, good proportionality of magnetic field, direct current, alternating current, direct current + alternating current measurement, fast response characteristics, simple structure, and good reliability.

In this case, the Hall sensors 330 and 340 may be provided in electronic circuitry in the controller 300 by specifying a sensor input order in advance.

When the motor 300 receives a signal from the Hall sensors 330 and 340 according to the sensor input order (for example, forward signal input) during motor operation, the controller 300 recognizes the normal operation, while receiving the signal in a reverse order. If input is received (eg reverse signal input), it can be recognized as reverse operation.

Accordingly, when the reverse signal is input to the control unit 300 by a predetermined number of times, the motor power is gradually increased to induce the motor driving in the forward direction, so that the electric vehicle or the electric motorcycle using the present embodiment stops on a hill road or the like. It is possible to prevent the jungle from starting.

7 is an exploded perspective view of the stator frame portion and the stator and cap portion.

Referring to FIG. 7, in this embodiment, the upper part of the winding part 230 installed in the stator frame part 210 of the stator 200 may be covered with a cap part 220 to compensate for magnetic loss. Since the stator frame portion 210 is connected to the motor shaft, heat dissipation may be improved as heat is transferred to the outside.

A circular first outer wall portion 218 and a first inner wall portion 219 are formed in the outer ring portion 213 of the stator frame portion 210.

The first outer wall portion 218 and the first inner wall portion 219 have a ring-shaped shape so as to maintain a spacing interval corresponding to the size of the stator core 213 for mounting the stator core 213 of the stator 200. Similarly, each of them extends along the outer or inner circumferential direction of the outer ring portion 213 while maintaining parallel to each other.

The seating grooves 214 and 214a of the stator frame portion 210 may have a height h for a spaced space from the outer ring portion 213 of the first outer wall portion 218 or the first inner wall portion 219. It is formed at the top, respectively.

By the height h of the stator frame 210, a clearance space may be secured inside the stator frame 210.

In this case, the first chamfer 214b may be formed at both sides of the seating grooves 214 and 214a at angles corresponding to the side inclination angles of the outer head or the inner head of the stator core 213, respectively.

Since the surface of the first chamfer 214b corresponds to an inclined surface having a relatively large surface area compared to a general plane, the first chamfer 214b may maintain a relatively excellent coupling state with excellent heat transfer efficiency. Here, the general plane may mean a rectangular cross section that is generated when a rectangular groove shape is generated in a direction perpendicular to the surface of the first outer wall portion 218 or the first inner wall portion 219.

Accordingly, the stator core 213 may be in direct contact with the stator frame portion 210 through the mounting grooves 214 and 214a even without a separate fixing protrusion or fixing means (not shown).

In this case, heat to be generated at the lower side of the stator core 213 is transferred directly to the stator frame portion 210, and thus can be transferred and radiated through the stator frame portion 210.

Meanwhile, the cap portion 220 includes a cap ring portion 227 having a circular ring plate shape that covers the upper portion of the winding portion 230, and a cap plane portion 227 for mounting of the stator core 213. The second outer wall portion 228 and the second inner wall portion 229 are formed at the outer circumference portion and the inner circumference portion, respectively.

The seating grooves 224 and 224a of the cap portion 220 may have a second outer wall portion 228 or a second inner wall portion of the cap portion 220 so as to secure a depth d for a spaced space from the cap plane portion 227. It is formed in the lower part of 229, respectively.

By the depth d of the cap 220, a clearance space may be secured inside the cap 220.

At this time, the second chamfer 224b is formed at both sides of the seating grooves 224 and 224a of the cap 220 at an angle corresponding to the side inclination angle of the outer head or the inner head of the stator core 213, respectively. Can be.

Since the surface of the second chamfer 224b also corresponds to the inclined surface having a relatively large surface area compared to the general plane, the heat transfer efficiency is relatively excellent and a stable coupling state can be maintained.

Accordingly, the separate stator core 213 may be in direct contact with the cap portion 220 through the mounting grooves 224 and 224a even without the fixing coupling protrusion or the fixing means.

In this case, heat to be generated at the upper side of the stator core 213 is directly transmitted to the cap portion 220, so that it can be transmitted and dissipated through the cap portion 220.

In particular, when the winding part 230 is assembled to the cap part 220, a gap space may also be formed between the inner surface of the cap part 220 and the upper portion of the winding part 230, so that heat is transferred through the gap space. Cooling convection may be generated smoothly, and as a result, it may be possible to increase the heat dissipation effect of the stator 200.

In addition, each of the stator frame portion 210 and the cap portion 220 of the stator 200 is made of an aluminum alloy material, the heat transfer efficiency is relatively good compared to other iron plate material can improve the heat dissipation characteristics.

In addition, the stator 200 may also have an effect of compensating the magnetic loss of the stator 200 by covering the upper and lower portions of the winding part 230 by the stator frame part 210 and the cap part 220. .

8 is a plan view illustrating an arrangement relationship between a stator, an internal rotor, and an external rotor.

Referring to FIG. 8, a virtual reference line P, which is a default value, passes through an axis center (eg, a center) of the motor shaft 120 and is respectively the center of the S pole inner magnet 152 of the inner rotor 150. It can be defined as passing through.

In addition, the external magnet placement reference line Q passing through the shaft center of the motor shaft 120 may be defined as passing through the center of the external rotor 130.

At this time, in this embodiment, the S pole inner magnet 152 of the inner rotor 150 and the N pole outer magnet 132 of the outer rotor 130 are centered on the stator core 231 of the stator 200. It may be twisted to achieve a predetermined magnet placement angle (M).

Here, the external magnet placement reference line Q for each of the external magnets 132 of the external rotor 130 may be installed in a state of leading or trailing by the magnet placement angle M relative to the virtual reference line P. FIG.

That is, since the N pole external magnet 132 of the outer rotor 130 does not correspond to the virtual reference line P for the inner rotor 150, it is installed to match the outer magnet arrangement reference line Q. As a result, the initial motor maneuverability is smooth, and torque ripple during operation can be reduced.

In addition, the embodiment of the present invention can reduce the torque ripple to reduce the motor vibration and noise.

9 is a plan view for explaining the stator core for the stator.

Referring to FIG. 9, each stator core 231 and 232 includes an intermediate portion 239 having core connections 233 and 234 protruding from both sides, and an outer head formed at one end of the intermediate portion 239. 238 and an inner head 237 formed at the other end of the intermediate portion 239.

Here, the plurality of stator cores 231 and 232 are formed to be integrally connected through the core connectors 233 and 234.

In particular, one core connecting portion 233 of one stator core 231, 232 and the other core connecting portion 234 of the other stator core 232 through the bent portion 235 having a relatively thin thickness compared to the thickness of the core connecting portion It is connected.

That is, the plurality of stator cores 231 and 232 according to the present embodiment may be integrally formed through the core connectors 233 and 234 and the bent portion 235.

Accordingly, as shown below in FIG. 9, the bent portion 235 may be used to correspond to the circumferential tilt of the stator 200, and a plurality of stator cores 231 and 232 may be easily assembled into one body. It becomes possible.

Insulators 240 and 241 may be coupled to intermediate portions 239 of the stator cores 231 and 232 with core connectors 233 and 234 interposed therebetween.

In addition, the winding wires 250 and 251 may be wound on the insulators 240 and 241.

In addition, through holes 236 are formed at both sides of the middle portion 239 of the stator cores 231 and 232 around the core connecting portion 233, respectively.

Here, the through hole 236 penetrates in the thickness direction of the stator core 231. The through hole 236 may play a role of preventing magnetic leakage toward the core connectors 233 and 234.

Hereinafter, the assembly state and the operating method according to the present embodiment will be described.

FIG. 10 is a cross-sectional view illustrating an assembling state and a method of operating the double rotor and single stator type BLDC motor shown in FIG. 1.

Referring to FIG. 10, the motor shaft 120 has a hollow or solid (not shown) shaft shape, and a shaft front part 123 and a shaft for supporting the bearing 114 for the casing cover 110. A stator shaft connecting portion 121 having a circular plate shape protruding from the circumferential surface of the rear portion of the front portion 123 (for example, the middle portion of the motor shaft), and a rear portion of the stator shaft connecting portion 121 (for example, the rear portion of the motor shaft). In order to support the bearing 104 for the casing body 100 may include a shaft rear portion 124 having a circular block shape of a relatively large diameter compared to the shaft front portion 123.

Here, the inlet hole 125 for passing the power line 190 for applying power to the control unit to be in close contact with the stator 200 may be formed in the shaft rear portion 124.

Both ends of the motor shaft 120 is further provided with a bolt hole for fastening the mounting bolt, it can be mounted or coupled to the place of use.

The bearings 104 and 114 of the motor shaft 120 may play a role of rotatably supporting the casing body 100 or the casing cover 110, respectively.

In addition, the stator 200 may be coupled to the motor shaft 120 through the boss 211 and the stator shaft connecting portion 121.

The outer rotor 130 may be disposed on the outer ring side with the winding portion 230 of the stator 200 at the center thereof, and the inner rotor 150 may have a play on the inner ring side of the stator 200. Can be placed while maintaining.

That is, the stator 200 may be disposed while maintaining a clearance in the space between the outer rotor 130 and the inner rotor 150.

When the motor control operation of the control unit in this arrangement state, by the outer rotor 130 and the inner rotor 150 in response to the operation of the stator 200, the casing cover 110 and the casing body 100 is the motor shaft Rotation is possible based on bearings 104 and 114 of 120.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, You will understand. For example, a person skilled in the art can change the material, size and the like of each constituent element depending on the application field or can combine or substitute the embodiments in a form not clearly disclosed in the embodiment of the present invention, Of the range. Therefore, it should be understood that the above-described embodiments are to be considered in all respects as illustrative and not restrictive, and that such modified embodiments are included in the technical idea described in the claims of the present invention.

100: casing body 107, 108: outer ring protrusion
110: casing cover 120: motor shaft
130: outer rotor 131: outer yoke
132: external magnet 135: elastic step
150: internal rotor 151: inner yoke
152: internal magnet 155: elastic step
160: magnet for sensing 200: stator
210: stator frame portion 220: cap portion
230: windings 231, 232: stator core
300: control unit 310: Hall IC
320: heat dissipation pad 330, 340: Hall sensor

Claims (6)

In a BLDC motor in which a motor casing rotates around a motor shaft,
A casing body disposed at the rear of the motor casing and integrally formed with the inner rotor and the outer rotor;
A casing cover coupled to the casing body at the front of the motor casing;
A stator disposed between an inner magnet arranged on the inner rotor and an outer magnet arranged on the outer rotor and coupled to the motor shaft;
It is installed on the stator, and includes a control unit for controlling the motor,
The inner magnet or the outer magnet is fixed by the elastic stepped portion formed on the inner rotor or the back yoke for the outer rotor
Double rotor and single stator type BLDC motors.
The method of claim 1,
The elastic stepped portion,
It is formed on the outer yoke or inner yoke to make a pair for each of the outer magnet and inner magnet.
Double rotor and single stator type BLDC motors. The method of claim 2,
The elastic stepped portion,
An elastic support protruding from the surface of the outer yoke or inner yoke;
Protruding from the end of the elastic support, characterized in that it comprises an inclined stepped jaw formed an inclined surface on the outer portion
Double rotor and single stator type BLDC motors.
The method of claim 2,
The elastic stepped portion,
Characterized in that the inclined stepped portion disposed between the elastic support for one magnet and the elastic support for the other magnet
Double rotor and single stator type BLDC motors.
The method of claim 2,
The elastic stepped portion,
After the molded or integrally formed with the inner yoke or the inner yoke, or separately manufactured by the injection molding in the manufacturing process of the outer yoke or the inner yoke, characterized in that formed by
Double rotor and single stator type BLDC motors.
The method of claim 2,
Between the outer yoke and the outer magnet,
Between the elastic step for the outer magnet and the outer magnet,
Between the inner yoke and the inner magnet,
In any one of the elastic step for the inner magnet and the inner magnet
Characterized in that the adhesive layer is further interposed
Double rotor and single stator type BLDC motors.

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